Prelubricated stock sheet and method and system for making the same

Abstract

A pre-lubricated stock sheet and a method and system for making the same are described. The pre-lubricated stock is generally in a coil wound form. The stock sheet can have opposing first and second sheet surfaces joined together by opposing side edges and opposing ends. Typically, the first and second sheet surfaces are substantially smooth and planar, wherein the sheet has 3 mg/foot2/side to about 200 mg/foot2/side of a solid lubricant having a melting temperature from about 80 to 212 degrees Fahrenheit. Moreover, the opposing side edges usually are substantially free of the solid lubricant. In some configurations, the stock sheet is an aluminum stock sheet, more particularly an aluminum can stock sheet. Furthermore, the lubricant can be in some configurations a food grade lubricant, that is qualifies a low volatile organic compound under one or more of municipal, state and federal governing authorities.

What is claimed is: 
     
       1. A method, comprising:
 heating a solid lubricant to form a liquid lubricant; 
 flowing the liquid lubricant to one or more pairs of applicators contained in an enclosure comprising a sheet inlet and a sheet outlet, wherein the enclosure is one or more of heated and insulated and wherein the enclosure is maintained at a temperature of from about 80 to 212 degrees Fahrenheit; 
 passing a stock sheet having opposing planar first and second stock sheet surfaces joined together by opposing stock sheet side edges and opposing stock sheet ends through the sheet inlet and the sheet outlet; 
 contacting the first and second stock sheet surfaces with the one or more pairs of applicators to form a lubricated stock sheet, wherein each of the one or more pairs of applicators deposits the liquid lubricant on the first and second stock sheet surfaces, and wherein no more than a total of from about 3 mg/foot 2 /side to about 200 mg/foot 2 /side of the liquid lubricant is deposited on the first and second stock sheet surfaces by the one or more pairs of applicators; and 
 winding the lubricated stock sheet into a coil. 
 
     
     
       2. The method of  claim 1 , wherein a melting temperature of the solid lubricant ranges from about 100 to about 200 degrees Fahrenheit, wherein no more than a total of from about 5 mg/foot 2 /side to about 110 mg/foot 2 /side of the liquid lubricant is deposited on the first and second stock sheet surfaces by the one or more pairs of applicators, and wherein the flowing and contacting further comprises:
 applying air pressure to a headspace of a lubricant-containing vessel to cause the liquid lubricant to flow pneumatically to the one or more pairs of applicators; 
 flowing the liquid lubricant from the lubricant-containing vessel to a perforated applicator element having first and second perforated element surfaces, wherein the perforated applicator element is in fluid communication with a porous applicator element having first and second porous element surfaces, wherein the liquid lubricant flows from the first perforated element surface to the second porous element surface and from the second porous element surface to the first porous element surface, and 
 wherein the contacting further comprises contacting the first porous element surface with the first and second stock sheet surfaces to deposit the liquid lubricant on the stock sheet. 
 
     
     
       3. The method of  claim 2 , wherein the first perforated element surface is in physical contact with the second porous element surface, wherein the melting temperature of the solid lubricant ranges from about 140 to about 195 degrees Fahrenheit, wherein the dispensed liquid lubricant forms a substantially continuous and substantially uniform lubricant layer on each of the first and second stock sheet surfaces of the lubricated stock sheet, wherein the perforated applicator element comprises a metallic material, a polymeric material, or a combination thereof, wherein the perforated applicator element comprises a plurality of apertures, a plurality of channels, or a combination thereof substantially uniformly distributed over the first and second perforated element surfaces, wherein the porous applicator element comprises a textile material, an organic polymeric material, an inorganic polymeric material, or a combination thereof, wherein the porous applicator element is permeable, porous, or both porous and permeable, wherein the enclosure is heated and further comprising:
 supplying thermal energy to the one or more pairs of applicators, wherein the thermal energy is supplied by one or more thermal heating elements contained within the enclosure and positioned between the one or more pairs of applicators and the enclosure; and 
 controlling, in response to input from a pressure indicator and by a pressure-adjusting element, a pressure applied to the first and second stock sheet surfaces by the porous applicator element to deposit the liquid lubricant on the stock sheet, wherein the pressure-adjusting element comprises one of an electromechanical device, a solenoid, a pneumatic device, or a combination thereof. 
 
     
     
       4. The method of  claim 1 , wherein a melting temperature of the solid lubricant ranges from about 80 to about 212 degrees Fahrenheit, wherein the first and second stock sheet surfaces, respectively, have first and second sheet surface areas, and wherein the contacting further comprises depositing the liquid lubricant on from about 99 to about 100% of the first and second sheet surface areas. 
     
     
       5. The method of  claim 1 , wherein the contacting further comprises contacting the stock sheet with the one or more pairs of applicators while the stock sheet is moving at a rate of about 100 to about 2,000 feet/minute, and wherein each of the first and second sheet surfaces comprises from about 60 mg/foot 2 /side to about 90 mg/foot 2 /side of the liquid lubricant. 
     
     
       6. The method of  claim 1 , wherein the enclosure is heated and further comprising supplying thermal energy to the one or more pairs of applicators, wherein the thermal energy is supplied by plural thermal heating elements positioned within the enclosure, wherein the plural heating elements are positioned symmetrically about the one or more pairs of applicators, and wherein each of the first and second sheet surfaces has from about 60 mg/foot 2 /side to about 90 mg/foot 2 /side of the liquid lubricant. 
     
     
       7. The method of  claim 1 , wherein each of the first and second sheet surfaces has from about 90 to about 100 mg/foot 2 /side with a variation in thickness of about ±10 mg/foot 2 /side of the liquid lubricant. 
     
     
       8. The method of  claim 1 , wherein one or more temperature sensing elements determine the enclosure temperature and a temperature controller maintains the enclosure temperature in the range of from about 80 to 212 degrees Fahrenheit and further comprising heating the enclosure using hot air produced from a heat exchanger fan subassembly comprising one or more fans and one or more heat exchanger elements. 
     
     
       9. The method of  claim 1 , wherein from about 3.7 to about 13.9 mg/square meter of the liquid lubricant is deposited on the stock sheet by the one or more pairs of applicators, wherein the one or more pairs of applicators contact the first and second sheet surfaces at a rate of from about 50 to about 6,000 feet/minute, wherein one or more of the following is true:
 (i) the solid lubricant is one or more of a NSF, Kosher or Halal approved food grade lubricant; 
 (ii) the solid lubricant is one of dioctyl sulfosuccinate, 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide, dioctyl sebacate, bis(2-ethylhexyl) sebacate, sebacic acid di(2-ethylhexyl) ester, hydrotreated heavy naphthenic petroleum distillates, alkenes having a carbon chain length greater than ten, and poly-α-olefin, petrolatum, and mixtures thereof; 
 (iii) the solid lubricate is FDA approved per 21 CFR 178.3910 Paragraph (b); and 
 (iv) the solid lubricant qualifies as a low volatile organic compound under one or more of municipal, state and federal governing authorities and wherein the heating comprises monitoring, by a temperature element, a temperature in a lubricant-heating vessel and heating, in response to input from a temperature controller in communication with the temperature element, the solid lubricant in the lubricant-heating vessel. 
 
     
     
       10. The method of  claim 1 , wherein the enclosure is heated and further comprising:
 supplying thermal energy to the one or more pairs of applicators, wherein the thermal energy is supplied by multiple thermal heating elements positioned within the enclosure, wherein the heating elements are positioned symmetrically about the one or more pairs of applicators, and wherein the stock sheet comprises one of steel, stainless steel, copper, tin, nickel, gold, platinum, rhodium, aluminum, an organic polymeric material, a metal, an alloyed metal, and a combination thereof. 
 
     
     
       11. The method of  claim 2 , wherein the heating comprises monitoring, by a first temperature element, a temperature in a lubricant-containing vessel and heating, in response to input from a temperature controller in communication with the first temperature element, the solid lubricant in the lubricant-containing vessel, wherein the heating comprises monitoring, by a second temperature element, a temperature in process piping transporting the liquid lubricant from the lubricant-containing vessel to the one or more pairs of applicators and heating, in response to input from the temperature controller in communication with the second temperature element, the lubricant in the process piping, and wherein, prior to the contacting, first and second side edges of the stock sheet are substantially free of the liquid and/or the solid lubricant. 
     
     
       12. The method of  claim 1 , wherein the heating comprises monitoring, by a first temperature element, a temperature in a lubricant-containing vessel and heating, in response to input from a temperature controller in communication with the first temperature element, the solid lubricant in the lubricant-containing vessel, wherein the heating comprises monitoring, by a second temperature element, a temperature in process piping transporting the liquid lubricant from the lubricant-containing vessel to the one or more pairs of applicators and heating, in response to input from the temperature controller in communication with the second temperature element, the lubricant in the process piping, and wherein opposing stock sheet side edges are substantially free of the liquid lubricant. 
     
     
       13. A method of  claim 2 , wherein the heating comprises:
 measuring, by a first temperature element, a first temperature in one or more lubricant heating vessels; 
 heating, in response to commands from a temperature controller, the solid lubricant in the one or more lubricant heating vessels to form the liquid lubricant; 
 transferring the liquid lubricant from the one or more lubricant heating vessels to the lubricant-containing vessel; 
 measuring, by a second temperature element, a second temperature of one or more heated transfer lines; 
 heating, in response to commands from the temperature controller, the one or more heated transfer lines; and 
 flowing the liquid lubricant from the lubricant-containing vessel to the one or more pairs of applicators through the one or more heated transfer lines. 
 
     
     
       14. A method comprising:
 heating a solid lubricant to form a liquid lubricant; 
 flowing pneumatically the liquid lubricant, under air pressure, from a heated lubricant-containing vessel through one or more heated transfer lines to one or more pairs of applicators comprising a perforated applicator element having first and second perforated element surfaces, wherein the perforated applicator element is in fluid communication with a porous applicator element having first and second porous element surfaces, wherein the liquid lubricant flows from the first perforated element surface to the second porous element surface and from the second porous element surface to the first porous element surface, and wherein the one or more pairs of applicators is contained in an enclosure comprising a sheet inlet to receive a stock sheet and a sheet outlet to output a lubricated stock sheet, wherein the enclosure is one or more of heated and insulated; 
 contacting the first porous element surface with the stock sheet comprising opposing substantially planar first and second surfaces to deposit the liquid lubricant on the first and second surfaces and form the lubricated stock sheet, wherein the contacting occurs at a temperature from about 80 to 212 degrees Fahrenheit; and 
 forming the lubricated stock sheet into a coil. 
 
     
     
       15. The method of  claim 14 , wherein a melting temperature of the solid lubricant ranges from about 100 to about 200 degrees Fahrenheit, wherein no more than a total of from about 5 mg/foot 2 /side to about 110 mg/foot 2 /side of the liquid lubricant is deposited on the stock sheet by the one or more pairs of applicators, and further comprising:
 applying air pressure to a headspace of the heated lubricant-containing vessel to cause pneumatically the liquid lubricant to flow under air pressure to the one or more pairs of applicators; 
 passing the stock sheet through the sheet inlet of the thermally insulated and heated enclosure and the sheet outlet configured for the stock sheet to traverse the enclosure and wherein the contacting occurs within the enclosure, wherein one or more temperature sensing elements determines an enclosure temperature and a temperature controller maintains the enclosure temperature in the range of from about 80 to 212 degrees Fahrenheit; and 
 controlling, in response to input from a pressure indicator, a pressure applied to the first and second stock sheet surfaces by the porous applicator element to deposit the liquid lubricant on the stock sheet, wherein the pressure adjusting element comprises one of an electromechanical device, a solenoid, a pneumatic device, or a combination thereof. 
 
     
     
       16. The method of  claim 15 , wherein the enclosure is heated, wherein the first perforated element surface is in contact with the second porous element surface, wherein the melting temperature of the solid lubricant ranges from about 140 to about 195 degrees Fahrenheit, wherein the dispensed liquid lubricant forms a substantially continuous and substantially uniform lubricant layer on the lubricated stock sheet, wherein the perforated applicator element comprises a metallic material, a polymeric material, or a combination thereof, wherein the perforated applicator element comprises a plurality of apertures, a plurality of channels, or a combination thereof substantially uniformly distributed over the first and second perforated element surfaces, wherein the porous applicator element comprises a textile material, an organic polymeric material, an inorganic polymeric material, or a combination thereof, and wherein the porous applicator element is permeable, porous, or both porous and permeable, and further comprising:
 supplying thermal energy to the one or more pairs of applicators, wherein the thermal energy is supplied by one or more heating elements, and wherein the one or more heating elements are contained within the enclosure in thermal proximity to the one or more pairs of applicators. 
 
     
     
       17. The method of  claim 14 , wherein from about 3.7 to about 13.9 mg/square meter of the liquid lubricant is deposited on the stock sheet by the one or more pairs of applicators, wherein the one or more pairs of applicators contact the first and second sheet surfaces at a rate of about 50 to about 6,000 feet/minute, wherein the heating step comprises monitoring, by a temperature element, a temperature in the heated lubricant-containing vessel and heating, in response to input from a temperature controller in communication with the temperature element, the solid lubricant in the heated lubricant-containing vessel, and wherein the contacting step further comprises one or more of the following:
 (i)depositing liquid lubricant on from about 99 to about 100% of the first and second sheet surfaces of the stock sheet; and 
 (ii) depositing no more than a total of from about 3 mg/foot 2 /side to about 200 mg/foot 2 /side of the liquid lubricant on the stock sheet by the one or more pairs of applicators. 
 
     
     
       18. The method of  claim 14 , wherein the heating step comprises monitoring, by a first temperature element, a temperature in the heated lubricant-containing vessel and heating, in response to input from a temperature controller in communication with the first temperature element, the solid lubricant in the heated lubricant-containing vessel, wherein the heating step comprises monitoring, by a second temperature element, a temperature in process piping transporting the liquid lubricant from the heated lubricant-containing vessel to the one or more pairs of applicators and heating, in response to input from the temperature controller in communication with the second temperature element, the process piping, and wherein each of the first and second surfaces of the stock sheet has from about 90 to about 100 mg/foot 2 /side with a variation in thickness of about ±10 mg/foot 2 /side of the liquid lubricant and wherein each of the first and second sheet surfaces has from about 60 mg/foot 2 /side to about 90 mg/foot 2 /side of the liquid lubricant. 
     
     
       19. A method, comprising:
 providing a stock sheet having opposing substantially planar first and second stock sheet surfaces joined together by opposing stock sheet side edges and opposing stock sheet ends; 
 passing the stock sheet through an enclosure comprising a sheet inlet and a sheet outlet configured for the stock sheet to traverse the enclosure and to maintain a liquid lubricant in liquid form, wherein the enclosure is one or more of heated and insulated; 
 contacting at least one of the first and second stock sheet surfaces with one or more pairs of applicators located within the enclosure to form a lubricated stock sheet, wherein each pair of applicators in the one or more pairs of applicators deposits the liquid lubricant to form a substantially continuous and substantially uniform lubricant layer on at least one of the first and second stock sheet surfaces, wherein the contacting occurs at a temperature of from about 80 to about 212 degrees Fahrenheit, wherein the liquid lubricant is a solid lubricant at ambient temperature, and wherein at least one of the following is true: 
 (i)the contacting occurs while the stock sheet is moving at a rate of about 100 to about 2,000 feet/minute; and 
 (ii) no more than a total of from about 3 mg/foot 2 /side to about 200 mg/foot 2 /side of the liquid lubricant is deposited on the stock sheet by the one or more pairs of applicators. 
 
     
     
       20. The method of  claim 19 , wherein one or more temperature sensing elements determine an enclosure temperature of the enclosure and a temperature controller maintains the enclosure temperature in the range of from about 80 to 212 degrees Fahrenheit and further comprising:
 applying air pressure to a headspace of a lubricant-containing vessel to pneumatically cause the liquid lubricant to flow, under air pressure, to the one or more pairs of applicators, wherein a temperature element monitors a temperature in the lubricant-containing vessel and, in response to input from the temperature element, a temperature controller in communication with the temperature element causes heating of a solid lubricant in the lubricant-containing vessel; 
 flowing the liquid lubricant from the lubricant-containing vessel to a perforated applicator element having first and second perforated element surfaces, wherein the perforated applicator element is in fluid communication with a porous applicator element having first and second porous element surfaces, wherein the liquid lubricant flows from the first perforated element surface to the second porous element surface and from the second porous element surface to the first porous element surface, and wherein the contacting further comprises: 
 contacting the first porous element surface with the stock sheet surface to deposit the liquid lubricant on the stock sheet; and 
 controlling, in response to input from a pressure indicator, a pressure applied to the stock sheet by the first porous element surface. 
 
     
     
       21. The method of  claim 19 , wherein the first and second stock sheet surfaces respectively have first and second sheet surface areas, and wherein the contacting further comprises depositing liquid lubricant on more than about 99% of the first and/or second sheet surface areas. 
     
     
       22. The method of  claim 19 , wherein the amount of liquid lubricant deposited on the first and/or second stock sheet surfaces varies no more than about ±10 mg/foot 2  and further comprising:
 measuring, by a first temperature element, a first temperature in one or more lubricant heating vessels; 
 heating, in response to commands from a temperature controller, a solid lubricant in the one or more lubricant heating vessels to form the liquid lubricant; 
 measuring, by a second temperature element, a second temperature of one or more heated transfer lines; 
 heating, in response to commands from the temperature controller, the one or more heated transfer lines; and 
 transferring the liquid lubricant from the one or more lubricant heating vessels to the one or more pairs of applicators through the one or more heated transfer lines.re heated transfer lines. 
 
     
     
       23. The method of  claim 19 , wherein the passing and contacting steps comprise: monitoring, by a first temperature element, a temperature in a lubricant-containing vessel and heating, in response to input from a temperature controller in communication with the first temperature element, a solid lubricant in the lubricant-containing vessel to form the liquid lubricant; monitoring, by a second temperature element, a temperature in process piping transporting the liquid lubricant from the lubricant-containing vessel to the one or more pairs of applicators; and heating, in response to input from the temperature controller in communication with the second temperature element, the lubricant in the process piping, wherein prior to the contacting step, first and second side edges of the stock sheet are substantially free of the liquid and/or the solid lubricant, and further comprising winding the lubricated stock sheet to form a coil of the lubricated stock sheet. 
     
     
       24. A method, comprising:
 heating a solid lubricant in a lubricant heating vessel to form a liquid lubricant; 
 transporting the liquid lubricant to a heated lubricant-containing vessel; 
 applying pressure to a headspace of the lubricant-containing vessel to cause pneumatically the liquid lubricant to flow under air pressure through heated piping to an enclosure comprising one or more pairs of applicators, wherein the enclosure is one or more of heated and insulated; 
 supplying thermal energy to the one or more pairs of applicators, wherein the thermal energy is supplied by one or more thermal heating elements contained within the enclosure and positioned near each of the one or more pairs of applicators; 
 passing a stock sheet comprising opposing substantially planar first and second stock sheet surfaces joined together by opposing stock sheet side edges and opposing stock sheet ends through the sheet inlet and the sheet outlet; 
 receiving, by a temperature controller, temperature measurements from temperature sensing elements in thermal communication with each of the lubricant heating vessel, heated lubricant-containing vessel, heated piping, and one or more thermal heating elements; 
 in response to the temperature measurements, controlling an amount of thermal energy supplied to a plurality of the lubricant heating vessel, heated lubricant-containing vessel, heated piping, and one or more thermal heating elements to maintain a temperature of the liquid lubricant above a melting point of the solid lubricant; and 
 winding the lubricated stock sheet into a coil. 
 
     
     
       25. The method of  claim 24 , wherein the melting temperature of the solid lubricant ranges from about 80 to 212 degrees Fahrenheit and further comprising:
 controlling, in response to input from a pressure indicator and by a pressure-adjusting element, a pressure applied to the first and second stock sheet surfaces by the one or more pairs of applicators to deposit the liquid lubricant on the stock sheet, wherein the pressure-adjusting element comprises an electromechanical device, a solenoid, a pneumatic device, or a combination thereof.